| Message ID | 110db78638438360da7e049343b06ea58af2a195.1689748694.git.yin31149@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/8] vhost: Add argument to vhost_svq_poll() | expand |
On Wed, Jul 19, 2023 at 9:54 AM Hawkins Jiawei <yin31149@gmail.com> wrote: > > Next patches in this series will delay the polling > and checking of buffers until either the SVQ is > full or control commands shadow buffers are full, > no longer perform an immediate poll and check of > the device's used buffers for each CVQ state load command. > > To achieve this, this patch exposes > vhost_svq_available_slots() and introduces a helper function, > allowing QEMU to know whether the SVQ is full. > > Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> Acked-by: Eugenio Pérez <eperezma@redhat.com> > --- > hw/virtio/vhost-shadow-virtqueue.c | 2 +- > hw/virtio/vhost-shadow-virtqueue.h | 1 + > net/vhost-vdpa.c | 9 +++++++++ > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c > index e731b1d2ea..fc5f408f77 100644 > --- a/hw/virtio/vhost-shadow-virtqueue.c > +++ b/hw/virtio/vhost-shadow-virtqueue.c > @@ -66,7 +66,7 @@ bool vhost_svq_valid_features(uint64_t features, Error **errp) > * > * @svq: The svq > */ > -static uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq) > +uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq) > { > return svq->num_free; > } > diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h > index 5bce67837b..19c842a15b 100644 > --- a/hw/virtio/vhost-shadow-virtqueue.h > +++ b/hw/virtio/vhost-shadow-virtqueue.h > @@ -114,6 +114,7 @@ typedef struct VhostShadowVirtqueue { > > bool vhost_svq_valid_features(uint64_t features, Error **errp); > > +uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq); > void vhost_svq_push_elem(VhostShadowVirtqueue *svq, > const VirtQueueElement *elem, uint32_t len); > int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > index 6b16c8ece0..dd71008e08 100644 > --- a/net/vhost-vdpa.c > +++ b/net/vhost-vdpa.c > @@ -620,6 +620,13 @@ static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, > return vhost_svq_poll(svq, 1); > } > > +/* Convenience wrapper to get number of available SVQ descriptors */ > +static uint16_t vhost_vdpa_net_svq_available_slots(VhostVDPAState *s) > +{ > + VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0); > + return vhost_svq_available_slots(svq); > +} > + > static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, > uint8_t cmd, const struct iovec *data_sg, > size_t data_num) > @@ -640,6 +647,8 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, > }; > > assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl)); > + /* Each CVQ command has one out descriptor and one in descriptor */ > + assert(vhost_vdpa_net_svq_available_slots(s) >= 2); > > /* pack the CVQ command header */ > memcpy(s->cvq_cmd_out_buffer, &ctrl, sizeof(ctrl)); > -- > 2.25.1 >
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index e731b1d2ea..fc5f408f77 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -66,7 +66,7 @@ bool vhost_svq_valid_features(uint64_t features, Error **errp) * * @svq: The svq */ -static uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq) +uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq) { return svq->num_free; } diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h index 5bce67837b..19c842a15b 100644 --- a/hw/virtio/vhost-shadow-virtqueue.h +++ b/hw/virtio/vhost-shadow-virtqueue.h @@ -114,6 +114,7 @@ typedef struct VhostShadowVirtqueue { bool vhost_svq_valid_features(uint64_t features, Error **errp); +uint16_t vhost_svq_available_slots(const VhostShadowVirtqueue *svq); void vhost_svq_push_elem(VhostShadowVirtqueue *svq, const VirtQueueElement *elem, uint32_t len); int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index 6b16c8ece0..dd71008e08 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -620,6 +620,13 @@ static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, return vhost_svq_poll(svq, 1); } +/* Convenience wrapper to get number of available SVQ descriptors */ +static uint16_t vhost_vdpa_net_svq_available_slots(VhostVDPAState *s) +{ + VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0); + return vhost_svq_available_slots(svq); +} + static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, uint8_t cmd, const struct iovec *data_sg, size_t data_num) @@ -640,6 +647,8 @@ static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class, }; assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl)); + /* Each CVQ command has one out descriptor and one in descriptor */ + assert(vhost_vdpa_net_svq_available_slots(s) >= 2); /* pack the CVQ command header */ memcpy(s->cvq_cmd_out_buffer, &ctrl, sizeof(ctrl));
Next patches in this series will delay the polling and checking of buffers until either the SVQ is full or control commands shadow buffers are full, no longer perform an immediate poll and check of the device's used buffers for each CVQ state load command. To achieve this, this patch exposes vhost_svq_available_slots() and introduces a helper function, allowing QEMU to know whether the SVQ is full. Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> --- hw/virtio/vhost-shadow-virtqueue.c | 2 +- hw/virtio/vhost-shadow-virtqueue.h | 1 + net/vhost-vdpa.c | 9 +++++++++ 3 files changed, 11 insertions(+), 1 deletion(-)